1. Technical Field
The present disclosure generally relates to the field of imaging, and, more particularly, imaging using controlled spherical aberration blurring.
2. Description of the Related Art
Imaging systems have an inherent limit in the ability to remain focused over long distances. The depth of field (DOF) of a reader is the distance between the nearest and farthest objects in a scene that appear acceptably sharp in an image. If a reader is used to decode optically encoded information (e.g., a barcode), increasing the DOF of the reader increases the zone in which the reader can reliably decode the encoded information.
Conventional techniques for extending the DOF of readers include physically moving lenses of the readers. Providing readers with movable lenses can increase the costs of manufacturing and maintaining such readers. Accordingly, it may be desirable to increase the DOF of readers in any lighting condition, including daylight, without employing movable lenses.